The Chemistry Core provides chemical services and logistical support to the constituent laboratories of the program project. Its major responsibility is the preparation of labeled and unlabeled eicosanoids, standards, metabolite analogues, and inhibitors in sufficient quantities for biological studies, as assay standards, for structure elucidations, and for methods development. All syntheses are patterned on existing synthetic routes taken from the literature or developed in Project VI. Generally, it is necessary to make modifications to the syntheses to accommodate the increased scale of the reactions or to permit the incorporation of labeled atoms. Appropriate analytical techniques, e.g., capillary GLC, HPLC, NMR, and mass spectroscopy, are used to verify product identity and to achieve acceptable levels of purity. The Core provides for the storage, packaging, and distribution of compounds to collaborating laboratories. In light of the limited availability of most eicosanoids from natural sources, the synthetic capabilities and resources of the core are essential for the successful conduct of the program project.